Broken arm victim Benjamin Macome is replaced at number 8 by Antonio Ahualli de Chazal whose two previous caps came in the South American Championship last month.
The only other alteration sees Oyonnax clubman Lucas González Amorosino start on the right wing in place of Santiago Cordero.
The Pumas have brought three new players onto the bench - front rowers Santiago Iglesias Valdez and Matias Diaz and outside back Matias Orlando who have 19 caps between them.
Iglesias Valdez, Orlando and starters Gabriel Ascarate and Lucas Noguera Paz all play their club rugby locally in Tucumán.
Argentina have held five previous Test matches against touring teams in Tucumán, with wins over Japan in 1993, Italy in 1995 and Wales in 2004 and two defeats to Scotland in 2010 and France in 2012.
The sides will be playing this Saturday for the Admiral William Brown Cup which is named in memory of the Irish-Argentine Navy admiral William Brown.
ARGENTINA Team & Replacements (v Ireland, Estadio José Fierro, Tucumán, Second Test, Saturday, June 14, kick-off 3.40pm local time/7.40pm Irish time):
15. Joaquin Tuculet (Unattached) 9
14. Lucas González Amorosino (Oyonnax) 31
13. Jerónimo de la Fuente (Duendes RC) 3
12. Gabriel Ascarate (Natación y Gimnasia) 13
11. Manuel Montero (Pucará) 11
10. Nicolás Sánchez (Bordeaux-Bègles) 19
9. Martín Landajo (CASI) 29 (capt)
1. Lucas Noguera Paz (Lince RC) 3
2. Matías Cortese (Liceo RC) 6
3. Ramiro Herrera (Castres Olympique) 1
4. Manuel Carizza (Stormers) 41
5. Tomas Lavanini (Hindú Club) 6
6. Rodrigo Baez (Liceo RC) 9
7. Tomás de la Vega (CUBA) 10
8. Antonio Ahualli de Chazal (SIC) 2
16. Santiago Iglesias Valdez (Universitario) 6
17. Bruno Postiglioni (La Plata RC) 11
18. Matías Díaz (Highlanders) 6
19. Matías Alemanno (La Tablada) 3
20. Javier Ortega Desio (Estudiantes de Paraná) 6
21. Tomás Cubelli (Belgrano Athletic) 23
22. Santiago González Iglesias (Asociación Alumni) 5
23. Matias Orlando (Huirapuca) 7
* Denotes uncapped player